Anyone with the first gen Prius had to replace the main battery?

A lot depends upon the service. As a general rule:

• heat is the enemy - Prius Battery Photos
• hills generate heat
• speeds above 70 mph generate heat

Since you live in San Francisco, there are two excellent, independent shops: Art's Automotive and Lucious Garage. Call them and they can use their instruments to measure your traction battery characteristics such as:

• minimum-maximum voltage pairs - how well the battery is balanced

I recently measured the Ahr capacity of my 19, module-pairs, ~3.5Ahr, which is OK but originally they were rated at 6.5Ahr. Still, at 133,000 miles, I have no complaints about the old battery performance but I want to do an experiment.

I'm replacing my NHW11 module battery with a Re-InVolt rebuilt pack with NHW20 modules. As I go through the process, I'm measuring the old and soon the new pack characteristics.

I have helped one boy who lives 50 miles South of Huntsville replace his traction battery with a Re-InVolt pack so this is no big deal. But at $1,700, it is in the same cost order of magnitude as say rebuilding a transmission.

You might want to read the thread about using a ScanGauge with your NHW11 Prius. We recently figured out how to read battery and other key system values and at $150-175, it is a good tool for general work.

Bob Wilson

 

You can find more information about the ReInVolt battery in other threads here, like Bob's just below. They are taking Gen 1 battery carriers and filling them with Gen 2 battery modules from low-mile salvage cars, which was already being bandied about for a while as a good idea because the Gen 2 modules had some improvements in internal resistance and heat control. It also seems to be a nice replacement package because they ship you the whole assembly to swap for your old one, which is less labor than the way a factory replacement arrives from Toyota. Another poster, jk450, is skeptical of whether the ReInVolt approach with Gen 2 modules offers any benefit over factory replacements from Toyota; Bob Wilson is a copious measurer of things, so I bet there will be interesting measurements posted in his thread once he gets his ReInVolt installed, though they'll still be measurements of just one old Gen 1 and one ReInVolt battery.

The battery isn't so much under the back seat, it's the hump you see across the front of the trunk, just behind the back seat. You remove the seat to get to some of the fasteners and connections, and the trunk carpet/trim to get to the rest. It's an easier-access, less-greasy job than a clutch or timing belt. On the other hand, your clutch can't drip potassium hydroxide on you (ouch!) or hit you with 300 volts, so you want to be sure you study up on the specific safety issues for this job. The manual recommends that you have >= 500 V insulated gloves in good condition. Under any but the strangest circumstances, with your key off, service plug handle flipped, and service plug pulled out, there should be 3 separate places inside the battery box where the circuit is interrupted before you even get near the connections, so the gloves are mostly insurance against some really bad coincidence. But absolutely do be sure to measure at the cable terminals with > 300 V insulated probes and get zero before you touch them with anything else; there are big capacitors in the inverter whose residual charge can take a while to drain.

If you will have any reason to open the battery case (as you would with a factory Toyota replacement), then the gloves are really not optional, and you will want to have a very tidy well-lighted workspace and give every safety instruction your undivided attention.

hope this helps,
-Chap

 

Hi eddy, did you buy the 2002 new? It should have had the (traction) battery cells resealed some time ago. If this has not been done, it is a free special service campaign with no time or odometer limit.

 

Eddy,I bought a battery from Reinvolt & they are fabulous to work with, very friendly & helpful. I live in an area where very few people own hybrids. Therefore, few people work on them. I decided to tackle the battery replacement myself. I know NOTHING about cars & I'm very much a 'girly girl', but I did it ALL BY MYSELF. The hardest part is lifting the battery in & out of the car because it weighs about 125 lbs. The staff at Reinvolt walked me through it & I took lots of pictures so I would be able to put everything back together correctly. Everything worked out fine & the battery comes with a 1 year warranty. Bottom line...Reinvolt is great & if I can do it, anybody with the will can do it.

 

Eddy, I purchased the ReInvolt battery and installed it into my 2002 Prius. If you can read, write and follow simple instructions, you too can do this. BTW, this was in October, and the price was $1500. The new Gen I battery from Toyota costs $2500 plus about $250 installation labor. The total shipping cost for shipping the re-built battery to me and shipping the old one back was around $280, roughly matching the dealer labor cost for the swap-out. Both the new Gen I battery and the remanufactured Gen II battery from ReInvolt are guaranteed for one year. Also the battery weighs 80 pounds, not 125 pounds, but still a little struggle to get it out but doable---I did it by myself and I'm 67; I heard about a woman in Texas who did the whole job by herself. Somewhere on this Gen I discussion board, someone has posted detailed instructions, plus ReInvolt provides a set of instructions. Also ReInvolt was immediately available to answer several questions I had during the replacement process. Most everyone agrees that the Gen II battery is superior to the Gen I battery: more power, no leakage, no degeneraation, & life expetancy twice as long. In further support of this thought, I spoke to a Toyota service manager at the Roseburg, CA, dealer (a high volume dealer); he said they've replaced 50-60 Gen I batteries but only 4 or five Gen II batteries. That tells a story right there. But the thing is, you don't know whether you're getting a re-built Gen II from a 2004 or 2009 model. But if the Gen II is known to last twice as long as a Gen I, maybe it'll be a wash if you get a 2004 model.

 

No. The definition of remanufacturing varies from state to state, but generally refers to the replacement of wear items, to the point that the expected performance of the reassembled equipment can be defined.

A battery cell's wear items are its electrolyte, its separators, and depending on degradation, the plates. These items, unfortunately, cannot be replaced in Prius modules.

Several companies sell used battery packs which have had the modules replaced with used modules from other packs, the connections between the modules replaced, and the modules recharged in an effort to rebalance the pack. These packs haven't been on the market long enough to determine average life span.

That's right. A few companies have claimed to sell packs are "remanufactured". As noted above, they are not; no matter how you look at them, they are packs constructed out of used modules.

 

Replaced main battery in 2001 Prius at 197,000 miles in January 2009 with Toyota battery. Warning lights came on in July 2010 indicating main battery failure. Symptoms are not consistent with original failure. Have been experimenting in hopes that the problem stems from 12V battery. Just replaced the 12V battery and warning lights are on again. I won't try another Toyota replacement battery.

 

I am also in Texas and was wondering how your replacement has gone over the last year. I'm about to do mine, and I think I'll go with the Reinvolt. Seems like a lot less hassle that rebuilding it myself.